Adjustable electromagnetic vibrator

ABSTRACT

The housing of the electromagnetic vibrator has an outer plate through which studs secured on the armature protrude. A weight is secured on the studs outside the housing. Further studs secured on the plate outside the housing mount the armature/weight assembly on the housing via counter-balancing springs. Nuts secured on the latter studs are adjustable to adjust vibration amplitude. Resilient bumpers may be provided to limit movement of the armature toward the core and coil and to limit movement of the weight toward the housing. The vibrator may use AC electric service, as is, or rectified to DC. The adjustable nuts also accommodate switching from AC to DC electrical service.

United States Patent [191 Mushrush 1 1 May 15, 1973 [54] ADJUSTABLE ELECTROMAGNETIC 3,404,299 10/1968 MacBlane ..310 17 VIBRATOR 3,522,460 8/1970 Spurlin ....310 29 3,575,620 4/1971 Braden ..3lO/29 [76] Inventor: George W. Mushrush, 12903 Sturbndge Road woodbndge, Primary ExaminerD. F. Duggan 22191 Attorney-Cushman, Darhy & Cushman [22] Filed: Mar. 1, 1972 [57] ABSTRACT [21] Appl. No.: 230,643

The housing of the electromagnetic vibrator has an outer plate through which studs secured on the arma- [52] US. Cl ..310/17, 310/29 mm protrude A weight is Secured on the Studs Outside llgt. Cl. th ho ing Further tuds e ured on the plate out- [58] Field of Search ..310/15, 17, 29, 32, side the housing mount h armature/weight assembly 310/28 on the housing via counter-balancing springs. Nuts secured on the latter studs are adjustable to adjust Referencfis Cited vibration amplitude. Resilient bumpers may be provided to limit movement of the armature toward the UNITED STATES PATENTS core and coil and to limit movement of the weight 2,694,156 11/1954 Cerminava ..310/29 X toward the housing. The vibrator may use AC electric 3,167,670 l/l965 Spurlin ..310/29 service, as is, or rectified to DC. The adjustable nuts 3,170,078 2/1965 Kllwhel 4 also accommodate switching from AC to DC electrical 3,333,219 7 1967 Makino ..310 29 UX Servim 3,345,525 10/1967 MacBlane ..3lO/l7 1 3 Claims, 2 Drawing Figures ADJUSTABLE ELECTROMAGNETIC VIBRATOR BACKGROUND OF THE INVENTION The present inventor is aware of the US. Pat. Nos. of MacBlane, 3,345,525, issued Oct. 3, 1967, and 3,404,299, issued Oct. 1, 1968, and the references cited therein. The vibrator of the present invention may be used for similar purposes at those disclosed in the MacBlane patents.

SUMMARY OF THE INVENTION The housing of the electromagnetic vibrator has an outer plate through which studs secured on the armature protrude. A weight is secured on the studs outside the housing. Further studs secured on the plate outside the housing mount the armature/weight assembly on the housing via counter-balancing springs. Nuts secured on the latter studs are adjustable to adjust vibration amplitude. Resilient bumpers may be provided to limit movement of the armature toward the core and coil and to limit movement of the weight toward the housing. The vibrator may use AC electric service, as is, or rectified to DC. The adjustable nuts also accommodate switching from AC to DC electrical service.

The principles of the invention will be further hereinafter discussed with reference to the drawing wherein a preferred embodiment is shown. The specifics illustrated in the drawing are intended to exemplify, rather than limit, aspects of the invention as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a diametral sectional view of the vibrator; and

FIG. 2 is a sectional view along line 2--2 of FIG. 1.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT The electromagnetic vibrator is shown including a spool-shaped housing 12 having a disk-shaped base plate 14, a tubular peripheral sidewall 16 and a diskshaped outer plate 18. Any two adjacent ones of the components 14, 16, 18 may be permanently secured together, e.g. by welding, and the other component removably secured thereto, e. g., by being bolted, screwed or clamped together.

Within the housing 12, an E-sectioned electromagnet core 20 is shown mounted on the base plate and provided with a wound coil 22. The power cable 24 for the coil 22 proceeds out through the housing at 26, to a source of electrical power 28. As shown, the power source 28 is AC current, and a rectifier 30 has been inserted to change the current to pulsating DC. Such rectifiers are commercially available, and the design thereof forms no part of the present invention. Preferably, the rectifier 30 is a plug-in type which may be removed from the power cable, or switching means 32 are provided to isolate the rectifier so the coil is provided with AC rather than pulsating DC current, at the operators option.

As shown, the core and coil terminate substantially below the housing outer plate 18 so a space is provided within the housing between the core/coil assembly and the housing outer plate. An armature 34 is shown disposed in that space. The armature is insufficiently thick to occupy all the space, so there is room for the armature to vibrate up and down within the space as pulsating current is sent through the coil.

Studs 36 are shown secured on the armature and projecting up through openings 38 in the housing outer plate 18 to outside the housing where the studs removably securely mount a weight 40. The latter is shown comprising a disk-shaped metal plate. There are also a plurality of studs 42 securely mounted on the housing outer plate 18 and extending axially upwardly therefrom through appropriate openings 44 through the weight 40. The openings 44 are oversize with respect to the studs 42 so the latter are slidably received through the former.

Each stud 42 carries a first compression coil spring 46 disposed between the housing outer plate 18 and the weight 40 and a second compression coil spring 48 disposed between the weight 40 and a nut or the like 50 adjustably secured on each stud 42.

It should be apparent that tightening the nuts 50 will lower the assembly 52 comprising the weight 40, studs 36 and armature 34, and that loosening the nuts 50 will raise that assembly 52. This provides a means for adjusting the air gap between the armature and the electromagnetic coil assembly, and thus affects the vibration amplitude of the assembly 52. The springs 46,48 thus adjustably counter-balance the assembly 52 to a null position. In some applications, as a lower extreme of vibration, the weight 40 or its mountings may be permitted to strike the housing 12. In other instances, that would prove too noisy or too destructive, whereupon resilient bumper means may be provided to cushion the assembly 52 at its lower extreme of vibration. In the instance depicted, the resilient bumper means are supplied by a plurality of resilient rubber plugs 56 mounted on the exterior of the plate 18 below the weight 40, among the studs 36, 42. Preferably, as shown, the plugs 56 are secured on threaded studs 58 provided with adjustable lock nut arrangements 60 which permit the heights of the bumpers to be adjusted.

When utilizing a rectifier the pulsations are cut in half compared to AC. (3,600 compared to 7,200). Rectified current, however, doubles the amplitude supply, the nuts 50 would be loosened to raise the assembly 52 to produce equivalent vibration effect for the body being vibrated. When the rectifier is removed from the line, the nuts 50 would be correspondingly tightened.

A sufficient number of studs 36, 42 and resilient bumpers 56 are provided to ensure substantially straight line reciprocation of the assembly 52.

The vibrator 10 is mounted to the apparatus to be vibrated, e.g. by bolting the housing base plate to the apparatus. It should be apparent that there is no rightside-up orientation for the device 10, since the counter-balancing of the assembly 52 permits the device to function in any spatial orientation. The device 10 is made of conventional materials for such electromagnetic vibrators. The vibrator 10 can be used with a relatively small air gap compared to prior devices; this results in a power saving.

It should now be apparent that the adjustable electromagnetic vibrator as described hereinabove possesses each of the attributes set forth in the specification under the heading Summary of the Invention hereinbefore. Because the adjustable electromagnetic vibrator of the invention can be modified to some extent without departing from the principles of the invention as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims.

What is claimed is:

1. An electromagnetic vibrator for imparting vibrations to a materials handling device, said vibrator comprising:

a housing including a base plate, a peripheral sidewall projecting axially from said base plate, and an outer plate on said sidewall near the end thereof opposite the base plate;

securement means on said housing for mounting the vibrator on a materials handling device;

a ferromagnetic core secured in said housing;

a wire coil received on said core facing outwardly of the housing base plate and constructed and arranged for connection to a supply of pulsating electric current;

a ferromagnetic armature disposed in the housing adjacent the core;

a weight disposed exteriorly of the housing, adjacent the outer plate;

first opening means being defined through the outer plate;

first stud means extending through the opening means and connecting the weight to the armature to provide an assembly capable of reciprocating as a unit; second opening means being defined through the weight;

second stud means mounted on the housing and extending through the second opening means; first compression coil spring means carried on the second stud means between the weight and the housing; securement means mounted on said second stud means on the opposite side of the weight from the housing, said securement means being mounted for adjustment toward and away from the housing; and second compression coil spring means carried on the second stud means between the weight and the securement means; whereby said assembly is counter-balanced to an adjustable level, and the securement means may be adjusted to vary said level to thereby vary the air gap between the armature and the core and coil. 2. The apparatus of claim 1 further including resilient means disposed between the weight and the housing to cushion abutment of the weight and the housing when said assembly is reciprocated toward the core and coil. 3. The apparatus of claim 2 wherein the resilient means comprise rubber bumpers and means heightadjustably mounting said rubber bumpers on the housing outer plate. 

1. An electromagnetic vibrator for imparting vibrations to a materials handling device, said vibrator comprising: a housing including a base plate, a peripheral sidewall projecting axially from said base plate, and an outer plate on said sidewall near the end thereof opposite the base plate; securement means on said housing for mounting the vibrator on a materials handling device; a ferromagnetic core secured in said housing; a wire coil received on said core facing outwardly of the housing base plate and constructed and arranged for connection to a supply of pulsating electric current; a ferromagnetic armature disposed in the housing adjacent the core; a weight disposed exteriorly of the housing, adjacent the outer plate; first opening means being defined through the outer plate; first stud means extending through the opening means and connecting the weight to the armature to provide an assembly capable of reciprocating as a unit; second opening means being defined through the weight; second stud means mounted on the housing and extending through the second opening means; first compression coil spring means carried on the second stud means between the weight and the housing; securement means mounted on said second stud means on the opposite side of the weight from the housing, said securement means being mounted for adjustment toward and away from the housing; and second compression coil spring means carried on the second stud means between the weight and the securement means; whereby said assembly is counter-balanced to an adjustable level, and the securement means may be adjusted to vary said level to thereby vary the air gap between the armature and the core and coil.
 2. The apparatus of claim 1 further including resilient means disposed between the weight and the housing to cushion abutment of the weight and the housing when said assembly is reciprocated toward the core and coil.
 3. The apparatus of claim 2 wherein the resilient means comprise rubber bumpers and means height-adjustably mounting said rubber bumpers on the housing outer plate. 